[llvm] [Support] Re-raise external signals (PR #125854)

[Alexandre Ganea via llvm-commits]

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@@ -468,8 +474,7 @@ void llvm::sys::AddSignalHandler(sys::SignalHandlerCallback FnPtr,
 
 #if ENABLE_BACKTRACES && defined(HAVE_BACKTRACE) &&                            \
     (defined(__linux__) || defined(__FreeBSD__) ||                             \
-     defined(__FreeBSD_kernel__) || defined(__NetBSD__) ||                     \
-     defined(__OpenBSD__) || defined(__DragonFly__))
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aganea wrote:

Why remove these?

https://github.com/llvm/llvm-project/pull/125854